After adding pop account, customer cannot delete or find a way to remove read messages.
The above symptom may occur on the following systems:
When you are in the inbox, you would not see any trash bin for you to remove any messages.
You have to press and hold the message for about 2 seconds before your mail is checked, selected and advanced option such as trash bin will show up (remove mail), etc.
In Figure 2, the trash bin is circled, click on it to delete your messages.